Rotary steam-engine.



No. 633,570. Patented Sept. 26, I899. J. F. CORNISH.

ROTARY STEAM ENGINE.

(Application filed Jan. 31, 1898.)

2 Sheets$heet. I.

(No Model.)

Patented Sept. 26, I899. J. F. CORNISH.

ROTARY STEAM ENGINE.

(Application filed Jan. 31, 1898.)

2 Sheets-Sheet 2.

(No Model.)

Nrren STATES PATENT OFFICE.

JOEL F. CORNISH, OF \VEST UNION, IOlVA.

ROTARY STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent No. 633,570, dated.September 26, 1899.

Application fil d January 31, 1898. Serial No. 668,689; (No model.)

To (1.7! II/71,077? it may concern.-

Be it known that I, JOEL F. CORNISH, a citizen of the United States,residing at \Vest Union, in the county of Fayette and State of Iowa,have invented a new and useful Rotary Steam-Engine, of which thefollowing is a specification.

My invention relates to improvements in rotary engines in which arotatable piston having one or more abutments operates in conjunctionwith a movable abutment adapted to move into the path of thepiston-abutments forming the heads between which the steam acts; and theobjects of my invention are, first, to obtain a continuous motion of thepiston; second, to construct an engine of wide range of power andadaptability cheaply, and, third, to obtain the greatest possibleexpansive power of steam. I attain these objects by the mechanismillustrated in the accompanying drawings, which are made a part hereof,and in which* Figure 1 is a vertical view in perspective of engine. Fig.2 is a vertical view in perspective of opposite side of engine from thatshown in Fig. 1.- Fig. 3 is a vertical crosssectional view of cylinderon line X Y of Fig. 1, with movable abutment located on top side. Fig. 1is a vertical sectional view on line 2 2 of Fig. 1, except of piston, ofwhich the side is shown. Figs. 5, 6, 7, 8, 9, 10,11,12, 13, and 14 aredetail views, which will be understood in connection with the followingdescription.

Similar letters and figures refer to similar parts throughout theseveral views.

Referring now to said drawings, lindicates the base of the engine, uponwhich is mounted the cylinder 2. Said cylinder 2 is providedconcentrically with shaft 3, having the usual bearings 4: and thepacking-glands 5. The interior of the cylinder 2 is provided with fiatsides, while the outer wall is approximately semicircular-incross-section,as shown.

It will be understood, of course, that the engine forming the subject ofthis invention can be used with a plurality of steam inlet and exhaustports as well as with one; but for convenience of illustration 1 haveselected that form of engine wherein it is run with one inlet and oneexhaust port and a piston provided with one abutment, although it isunderstood that this invention is not limited to i such construction norto other details exceptthose that are specially pointed out in theclaims.

At some point on the said cylinder 2 it is provided 'with steam-inletports, situated at the inner end of passage 6, and exhaust-ports 7, theinlet-ports being in side walls of cylinder 2 and the exhaust-ports alsoinside wall and nearly opposite the inletports. The piston 8 is carriedby shaft 2, the sides of which fit closely within the cylinder, and theouter face of same is semicircular in form, corresponding in form withthe outer wall of the cylinder.

To maintain a tight joint between the sides of the piston 8 and thesides of the cylinder 2, the said piston is provided on each sidelaterally with grooves 9, that communicate by means of passages 10 withthe steam-space between the piston and cylinder, while within saidgrooves are situated the metallic packing-rings 11, which, under the.influence of the steam-pressure, are forced against the side walls ofthe cylinder and maintain a tight joint, while within the passages 10,and near the on ter ends thereof,are placed check-valves A, which allowsthe passage of steam to the rear faces of packing-rings 11, but preventsthe steam from passing outwardly through same and escaping by way of theexhaust. The said piston 8 is provided with an abutment l2,that fitsclosely within the outer wall of the cylinder and is provided withpackingstrips 13, situated within grooves 14 in said abutment. The endsof grooves 14 are provided with chamfered recesses 15,into which thechamfered lugs 16 of packing-strips 13 are situated. These grooves 14also connect by means of passages 16:} with the steam-space between thepiston and cylinder, and under passages 16:} are forced outwardlyagainst the walls of the cylinder to maintain a tight joint between theabutment 12 and the cylinder, the walls of the cylinder holdingpackingstrips 13 within the grooves 14, the chamfered lug 16 inchamfered groove also holding strips 123 in position, but allowing sameto expand transversely and outwardly.

It will be noticed that packing-rings 11 are provided with recesses 1818 in same on the side adjacent to abutment 12, which receive the innerends 17 of the packing-strips 13,

the influence of the steam-pressure throughwhich are extended inwardlypast lug 16 and into said recesses 18 for the purpose of maintaining atight joint between the rings 11 and strips 13. That part ofpacking-rings 11 between the recesses 18 18 is provided on its rear facewith a projection or lug a, which fits closely within recess b, situatedin the bottoni of groove 9 of said piston 8, which lug a under theinfluence of the steam-pressure is forced against the side of recess 1)and prevents the passage of steam underneath the packing-rings 11 toopposite sides of abutment 12.

The cylinder 2 is provided with a steamchest or valve-chamber 19, thatis provided near its outer end with the steam-inlet port 20 forsupplying steam thereto, and is also provided with passages 6 6, nearthe central or middle part and on opposite sides thereof, leading fromthe steam-space in said valvechamber 19 to the steam-space in thecylinder 2.

The means of communication between the steam-inlet 20 and passages 6 isthrough the the valve-chamber 19, in which is situated the cylindricalvalve 21. The inlet 20 communicates with the outer end portion ofvalvechamber 19 and through the side thereof, while the passages 6communicate with the opposite sides of valve-chamber and near the innerend thereof, it being noted that the axis of the valve-chamber 19 isradially arranged with reference to the cylinder. The valve 21 iscylindrical and is capable of both a rotary and longitudinal movementwithin the valvechamber, such movement being controlled by a stem 22,that passes through the outer end 23 of valve-chamber 19, approvedpacking of course being used to prevent the escape of steam. This valve21 is hollow and open at both ends, while at its center portion is alateral port 24 for establishing communication with the passages 6.

In the outer side of valve 21 and side on which port 24 is situated iscountersink 25, into which plate 26 is fitted closely and is held insaid countersink by the walls of valvechamber, but which under theinfluence of the steam-pressure through ports or passages 27 in andthrough the bottom of said countersink to the steam space within valve21 presses plate 26 outwardly against the.walls of the valve-chamber andmaintains a tight joint at all times between the valve 21 and the wallsof valve-chamber 19, thus allowing for wear of valve within thevalve-chamber. Mounted upon the outer wall of cylinder 2 is recess 29,within which is situated the movable abutment 27, that is adapted tomove into the path of the piston-abutment 12 between the inlet andexhaust ports and serves, in connection with abutment 12 of the piston8, to form the heads between which the steam acts. This abutment 27moves in guidegrooves 28 in the sides of the cylinder and can moveoutwardly into. recess 29, provided for same, to allow abutment 12 topass that point seams in its revolution. The said abutment 27 issemicircular in form at its inner end, corresponding in form to the formof the outer face of the piston 8. The said abutment is also provided onits inner end with packing-strip 29%, situated within a groove therein,and serves to maintain a tight joint between the abutment 27 and thepiston.

The movement of abutment 27 is controlled by a stem 30, rigidly attachedto abutment 27, that extends outwardly through stuffing-box 31 in theouter wall of recess 29, the said stem 30 being connected to shaft 3 ofthe piston 8 by mechanism for moving same, and consequently abutment 27,in and out of the path of the piston-abutment S at each revolution ofthe piston. I will now describe this mechanism.

Secured to shaft 3 eccentrically is round wheel 32, provided upon itsouter face or periphery with gearing cogs or teeth. On stationary axle33, which is made integral with plate 34, which is secured to side ofcylinder by stud-bolts 35, is gear-wheel36, ellipsoidal in form and ofthe same circumference as wheel 32 and having the same number of cogs orteeth and rotates upon said axle 33 eccentrically, the cogs or teethgearing into and meshing with the cogs in wheel 32, producing a motionof variable speed, being very slow through three-fourths of itsrevolution and very fast during the remaining one-fourth of theIBVOllltlOll of wheel Secured upon wheel 36, distant from center of axleupon which said wheel is secured a little greater than one-half thedesired movement of abutment 27, is crank-pin 37, to which is adjustablyconnected link 38, which is adj ustably secured by pin to cross-head 39on radial bar 40, radial bar 40 being pivoted at its outer end upon axle41, secured to side of cylinder 2.

Adjustably secured by pin to cross-head 39 is connecting-rod 42, to theouterend of which is secured by pivot-joint a laterally-extending arm43, which is secured to stem 30 of abutment 27. The outer and sidewalls. of cylinder 2 at that part where abutment 27 is situated arerecessed a little, so that abutment 12, with its packing-strip 14, maypass that part of the cylinder where abutment 27 and the inlet andexhaust ports are situated without interference, though packing-strips14 may be fully expanded by the centrifugal force caused by the rotationof the piston.

I will now proceed to describe the construc tion of the device forcontrolling the inlet and supply and cutoff of the steam.

The shaft 3 is provided on the side of the cylinder 2 on whichsteam-chest or valvechamber is situated with the spur-geared eccentricwheels 32 and 36 and the combination of crank-pin 37, link38 and pin,crosshead 39, radial bar 40, axle 41, and connect ing-rod 42, thesame'as heretofore described for movingabutment 27, except round wheel32'is not rigidly secured to shaft 3,but is allowed to turn one-half wayaround upon shaft 3 by mechanism shown in Fig. 7.

At diametrically opposite points on the side of shaft 3, at that portionwhere same passes through eccentric wheel 32, same is provided withrigid lugs or pins 43. The aperture in wheel 32 which receives shaft 3has countersink 44 around same on the side of the wheel adjacent tocylinder. Situated within said countersink 44 on diametrically oppositesides are lugs 45, which extend inward to shaft 3, and as shaft 3 turnswithin said wheel 32 the lugs 45 engage the lugs or pins 43 on shaft 3and prevent shaft 3 from turning more than one-half a revolution withoutcarrying with it wheel 32. The purpose of this device is to maintain thesame relative movement of abutment 27 and valve 21 when engine isrunning in either direction. The outer end of connecting-rod 42 isconnected with a laterally-extending arm 46 by a pivot-joint,theopposite end of said arm being adjustably connected with the stem 22 ofvalve 21. The connection between said arm 46 and stem 22 consists of acollar 47, rigidly secured to stem 22 and provided with annularshoulders 48, between which is situated a rotatable screwthreaded sleeve49, which is provided on its outer end with hand-wheel 50, by means ofwhich said sleeve may be turned, while the arm 46 is provided with ascrew-threaded aperture to receive the screw-threaded sleeve 49. In thisway itWill be seen that by turning the hand-wheel 50 the sleeve 49, andconsequently the stem 22, is raised or lowered in an obvious manner.This has the effect, it will be seen, of controlling the supply andcut-off of the steam by opening the means of communication betweenvalve-chamber 19 and the steam-space in cylinder through port 24 invalve 21 and the passages 6, leading to cylinder, the means ofcommunication being greater or less as saidvalve 21 is raised orlowered.

The stem 22 extends outwardly beyond arm 46 and is provided with asquared end portion 51,that passes through an opening of similar shapein the bushing 52, carried by the overhanging arm 53. This bushing canturn within the opening in the arm and is rigidly attached to lever 54,bymeans of which stem 22, and consequently valve 21, is made to turn orrotate with the valve-chamber 19, thus moving port 24 out of alinementwith the passages 6 and shutting off all-means of communication betweenvalve-chamber 19 and cylinder, or opening said means of communication ina greater or less degree as may be desired. This has the effect, it willbe seen, of controlling the amount of steam entering cylinder. Theexhaust ports communicate with a cylindrical valvechamher 55,that isconveniently castintegral with plate 56, which is bolted to outside ofcylinder, as shown. This valve-chamber is provided with openings 57,situated in alinement with the exhaust-ports 7, and is provided with aport 58, communicating with an exhaust pipe or passage 50. Thecylindrical valve is situated within the valve-chamber 55 and isprovided with oppositely-situated ports 61 to establish communicationwith the openings 57, while about midway between the ends of valve 60 isthe opening 62, that is situated in alinement with port 58. Valve 60 isprovided with a stem 63, that passes through an opening in head ofvalve-chamber 55, and to which is secured bevel gear'wh eel 64, whichgears into and is turned by a similar bevel gear-wheel 65 of twice thediameter of Wheel 64 and is secured to rod 66, the inner end of which isheld in position by box 67, secured to side of cylinder, and extendsoutwardly to cross-head 68 on the outwardly-extendin g arm 69, securedto side of cylinder and through an opening in said crosshead 68. I

Secured to the outer end of rod 66 is bar 70, the outer end of which issecured by joint to a curved bar 71, the opposite end of which issecured to an extension 72 of lever 54, the relative length of theextension 72 of lever 54 and the bar being such that while the end oflever 54, attached to curved bar 71, moves through one-half a circle bar70 moves through only one one-fourth of a circle, so that the relativepositions of valve 21 and valve65 will be maintained at all times.

The operation of the machine is as follows: Steam being admitted tovalve-chamber 19 through steamdnletpassage 2O fills said valvechamberand the interior of valve 21 therein situated. By means ofoperating-lever 54 valve 21 is turned to bring the port 24 in said valveinto communication with passage 6, leading to the steam-space ofcylinder 2, which is filled with steam. The steam acting betweenabutment 27 and abutment 12 of the piston the packing-strips 13 of saidabutment are expanded against the walls of the cylinder, as are alsopacking-rings 11 of the piston and packing-strip 29-} of abutment 27.The abutment 12 being free to move it is forced to revolve within thecylinder, carrying with it the piston 8 and of course shaft 3. As soonas abutment 12 has passed the open exhaustport the steam is exhaustedthrough said exhaust-port into exhaust-chamber 55 and escapes by way ofopening in valve 60 and exhaust-pipe 58. The abutment 27 is now freedfrom steam-pressure, and the same is now moved outwardly into recess 29by means of the eccentric gear-wheels 32 and 36 and the connectionsbetween same and stem 36 of abutment 27. As soon as abutment 12 haspassed the abutment 27 same is moved inwardly into the path of thepiston-abutment by the same mechanism that/moved it outwardly, and steamis again admitted and the process repeated, it being noted that themomentum of the piston carries same from the time exhaust-port is passeduntil again acted upon by the steam, being about one-fourth therevolution. It will also be noted that before abutment 12 passes-theopen exhaust-port on the opposite side of the movable abutment 27 fromthat which is taking steam the means of communication betweenvalve-chamber 19 and the cylinder is closed by the moving of valve 21inwardly, so that port 24 in valve 21 and the passage 6 are not incommunication, though by means of the adjustable connection between rod42 and stem 22 of valve 21 the steam may be cut 0% after piston hastraveled one-fourth revolution after taking steam. By means of lever 54valve 21 may be turned one-half way around, thus throwing the port 24 insaid valve into communication with passage 6 on the opposite side ofvalve-chamber, and steam is supplied to cylinder on opposite side ofabutment 27. At the same time,by means of the extension 72 of said leverand the connections with valve 60, the exhaust-port on the side ofabutment 27 taking steam is closed and the exhaust-port on the oppositeside of said abutment is opened and the engine is reversed or travelingin the opposite direction. By turning valve 21 onefourth way around port24 of said valve is thrown out of alinement with either of passages 6and steam is shut off. It will be noted that the round eccentric-wheel32 is not rigidly attached to shaft 3, but is allowed to turn about onehundred and seventy-five degrees on said shaft. This gives the samerelative movement of valve 21 and abutment 27 when engine is running ineither direction, the longest eccentrical radius of wheel 32 and thelongest eccentrical radius of wheel 32 being at quadrature when engineis running either way. Thus it will be seen that the operator hascomplete control of his machine, that no more steam need be used thannecessary to do the required labor, and that the greatest expansivepower of steam will be utilized. It will alsobe noted that by arrangingtwo or more of these engines on the same shaft a continuous steampressure during the entire revolution will be had, and consequentlygreat power will result.

I am aware that prior to my invention rotary engines have been made witha movable abutment adapted to move into the path of the piston-abutmentand a rotatable piston provided with an abutment. I therefore do notclaim such a combination broadly; but

What I claim as my invention, and desire to secure by Letters Patent, is

1.. In a rotary engine a rotatable piston situated therein having anabutment provided with packing-strips, annular grooves in the sides ofsaid piston, a recess in the bottom of said grooves at that partadjacent to the abutment, annular packing-rings, situated within saidgrooves, having recesses to receive the inner end of packing-strips ofabutment, and

.a lug or pin secured to the rear face of said annular packing-rings,between the aforesaid recesses and extending at right angles to theplane of said annular rings into recess provided for same, in the bottomof said annular grooves substantially as set forth.

2. In a rotary engine a cylinder a rotatable piston having an abutment amovable abutment adapted to move into the path of the piston-abutment,and a connection between said rotatable piston and said movable abutmentembracing round and ellipsoidal eccentric gear-wheels for moving thelatter.

3. In a rotary engine a cylinder, a rotatable piston having abutment, amovable abutment adapted to move in guide-grooves in the sides of saidcylinder in and out of the path of said piston-abutment, by reason ofthe connection between said piston and said movable abutment, embracingshaft 3, eccentric gearwheels 32, and 36, crank-pin 37, link and pin 38,cross-head 39, radial bar 40, connectingrod 42, the laterally-extendingarm 43, and stem 30 substantially as described.

4. In a rotary engine a valve-casing having a hollow cylindrical valvesituated therein, a port in the side of said valve, amovable platefitted into countersink in the side of said valve, with a port in samein alinement with port in said valve, and passages leading from theinterior of said valve to the rear face of said plate substantially asset forth.

5. In a rotary engine, acylindera rotatable piston situated therein, alongitudinally movable and rotatable valve havinga valve-stem, and aconnection between said valve-stem and said rotatable piston embracinground and ellipsoidal eccentric gearwheels for moving the latter.

6. The combination in a rotaryengine of a cylinder, a rotatable pistonprovided with a shaft rigidly secured to the same concentrically, alongitudinally movable and rotatable valve, a connection between saidshaft and said valve for moving the latter, embracing an eccentricellipsoidal gear-Wheel driven by an eccentric round gear-wheel looselysecured to said shaft by pins upon said shaft which engage lugs situatedin countersink in said round wheel substantially as set forth.

7. In a rotary engine a cylinder provided with a rotatable pistontherein situated, a movable abutment mounted in the outer wall ofcylinder, steam-inlet ports in said cylinder on opposite sides of saidabutment, a valve-chamber with cylindrical valve therein situatedcapable of being rotated by operating-lever, a means of communicationbetween said valve-chamber and the cylinder through port in said valve,and passages leading from said valve chamber to cylinder, exhaustportson opposite sides of said movable abutment, an exhaust-valve chambercontaining, a cylindrical valve with oppositely-situated ports and anopening near-its middle communicating with exhaust-passage, and aconnection between said exhaust-valve and said operating-lever wherebysame is rotated in conjunction with the said steam-inlet valvecontrolling the supply of steam to said cylinstem, a rotatablescrew-threaded sleeve carried by said collar, a hand -Wheel upon saidsleeve and a movable rod having a laterallyextending' arm provided witha screw-threaded aperture in which said screw-threaded sleeve issituated.

lronL F. OORNISH.

YVitnesses:

XV. J. AINSWORTH, CHAS. RUIEHE.

